package com.sttx.bookmanager.util.http;

import java.io.ByteArrayOutputStream;
import java.io.DataOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.SocketTimeoutException;
import java.net.URL;
import java.net.URLEncoder;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;

import javax.imageio.ImageIO;
import javax.imageio.ImageReader;
import javax.imageio.stream.ImageInputStream;

public class HttpPostUtil {
    URL url;
    HttpURLConnection conn;
    String boundary = "--------httppost123";
    Map<String, String> textParams = new HashMap<String, String>();
    Map<String, File> fileparams = new HashMap<String, File>();
    DataOutputStream ds;

    public HttpPostUtil(String url) throws Exception {
        this.url = new URL(url);
    }

    // 重新设置要请求的服务器地址，即上传文件的地址。
    public void setUrl(String url) throws Exception {
        this.url = new URL(url);
    }

    // 增加一个普通字符串数据到form表单数据中
    public void addTextParameter(String name, String value) {
        textParams.put(name, value);
    }

    // 增加一个文件到form表单数据中
    public void addFileParameter(String name, File value) {
        fileparams.put(name, value);
    }

    // 清空所有已添加的form表单数据
    public void clearAllParameters() {
        textParams.clear();
        fileparams.clear();
    }

    // 发送数据到服务器，返回一个字节包含服务器的返回结果的数组
    public byte[] send() throws Exception {
        initConnection();
        try {
            conn.connect();
        } catch (SocketTimeoutException e) {
            // something
            throw new RuntimeException();
        }
        ds = new DataOutputStream(conn.getOutputStream());
        writeFileParams();
        InputStream in = conn.getInputStream();
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        int b;
        while ((b = in.read()) != -1) {
            out.write(b);
        }
        conn.disconnect();
        return out.toByteArray();
    }

    // 文件上传的connection的一些必须设置
    private void initConnection() throws Exception {
        conn = (HttpURLConnection) this.url.openConnection();
        conn.setDoOutput(true);
        conn.setUseCaches(false);
        conn.setConnectTimeout(10000); // 连接超时为10秒
        conn.setRequestMethod("POST");
        conn.setRequestProperty("Content-Type", "multipart/form-data; boundary=" + boundary);
    }

    // 普通字符串数据
    private void writeStringParams() throws Exception {
        Set<String> keySet = textParams.keySet();
        for (Iterator<String> it = keySet.iterator(); it.hasNext();) {
            String name = it.next();
            String value = textParams.get(name);
            ds.writeBytes("--" + boundary + "\r\n");
            ds.writeBytes("Content-Disposition: form-data; name=\"" + name + "\"\r\n");
            ds.writeBytes("\r\n");
            ds.writeBytes(encode(value) + "\r\n");
        }
    }

    // 文件数据
    private void writeFileParams() throws Exception {
        Set<String> keySet = fileparams.keySet();
        for (Iterator<String> it = keySet.iterator(); it.hasNext();) {
            String name = it.next();
            File value = fileparams.get(name);
            ds.write(getBytes(value));
            /*
             * ds.writeBytes("--" + boundary + "\r\n"); ds.writeBytes(
             * "Content-Disposition: form-data; name=\"" + name +
             * "\"; filename=\"" + encode(value.getName()) + "\"\r\n");
             * ds.writeBytes("Content-Type: " + getContentType(value) + "\r\n");
             * ds.writeBytes("\r\n"); ds.writeBytes("\r\n");
             */
        }
    }

    // 获取文件的上传类型，图片格式为image/png,image/jpg等。非图片为application/octet-stream
    private String getContentType(File f) throws Exception {

        // return "application/octet-stream"; //
        // 此行不再细分是否为图片，全部作为application/octet-stream 类型
        ImageInputStream imagein = ImageIO.createImageInputStream(f);
        if (imagein == null) {
            return "application/octet-stream";
        }
        Iterator<ImageReader> it = ImageIO.getImageReaders(imagein);
        if (!it.hasNext()) {
            imagein.close();
            return "application/octet-stream";
        }
        imagein.close();
        return "image/" + it.next().getFormatName().toLowerCase();// 将FormatName返回的值转换成小写，默认为大写

    }

    // 把文件转换成字节数组
    private byte[] getBytes(File f) throws Exception {
        FileInputStream in = new FileInputStream(f);
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        byte[] b = new byte[1024];
        int n;
        while ((n = in.read(b)) != -1) {
            out.write(b, 0, n);
        }
        in.close();
        return out.toByteArray();
    }

    // 添加结尾数据
    private void paramsEnd() throws Exception {
        ds.writeBytes("--" + boundary + "--" + "\r\n");
        ds.writeBytes("\r\n");
    }

    // 对包含中文的字符串进行转码，此为UTF-8。服务器那边要进行一次解码
    private String encode(String value) throws Exception {
        return URLEncoder.encode(value, "UTF-8");
    }

    // public static void main(String[] args) throws Exception {
    // HttpPostUtil u = new HttpPostUtil("http://localhost:3000/up_load");
    // u.addFileParameter("img", new File("D:\\素材\\圆月.jpg"));
    // u.addTextParameter("text", "中文");
    // byte[] b = u.send();
    // String result = new String(b);
    // System.out.println(result);
    //
    // }

}